Development of polymeric nanofibers is of great scientific and technological interest because of their wide-range applications in biomedicine and biotechnology. Particularly, composite nanofibers derived from natural and synthetic polymers, capitalizing on the favorable biological properties of the natural polymer and mechanical strength of the synthetic polymer, represents a major advancement in tissue engineering and regenerative medicine. However, the development of well-blended natural-synthetic composite polymers remains a great challenge due to the poor miscibility of the component polymers, where natural polymers are generally soluble in aqueous and polar solvents, but most synthetic polymers are not. Poorly blended polymeric nanofibers exhibit weak mechanical strength and uncontrollable material properties as a result of inhomogeneity.
Large-gap nerve damage that cannot be directly repaired with sutures has typically been treated using nerve autografts, but this technique suffers from donor site morbidity, inadequate return of function, aberrant regeneration, and shortage of donor tissue. An alternative approach is to use a nerve guide conduit serving both to promote nerve regeneration and to provide a pathway for nerve outgrowth. A number of polymeric nanofibers, including poly(caprolactone) (PCL), poly(lactic acid) (PLLA), poly(lactic-co-glycolic acid) (PLGA), collagen, and chitosan, are emerging as promising candidates for nerve repair. While the advances in nerve regeneration are encouraging, few of current nerve guide materials succeed in showing structural stability and pliability in physiological environments.
Common problems confronted in application of artificial nerve guides as a result of unsatisfactory mechanical or biological properties of nerve conduits include structural collapse, material swelling, early resorption, and release of cytotoxic degradation products.
Despite the advances in materials for nerve regeneration, a need exist for nerve regeneration conduits having biocompatibility and mechanical strength, and that support nerve growth. The present invention seeks to fulfill this need and provides further related advantages.